1. Field of the Invention
This invention relates to a hand movement detecting and correcting apparatus for use in a camera or the like, and in particular, relates to a hand movement detecting and correcting apparatus capable of quickly correcting hand movement by detecting mechanical movement of the camera and image movement of an object image formed on an optical image forming device of the camera.
2. Discussion of the Background
In an optical device such as a camera and so on, movement of the optical device caused by hand movement raises a problem. To overcome such a problem, the below described devices have been proposed. First, as illustrated in Japanese Patent Application Publication Number 56-21133, movement of the optical device is suppressed by detecting the movement of the optical device itself using a gyroscope, and by changing a whole or part of the optical unit, for example a lens, to change a position of an optical image in the camera based on the detection. Thus, the hand movement can be compensated for.
Second, as illustrated in Japanese Patent Application laid open No. 7-177419 entitled xe2x80x9cTelevision Cameraxe2x80x9d, an optical image of an object, which is photographed on an image sensing element, is changed when movement occurs in a manner as described below. Namely, first, an object signal of the optical image is obtained from the image sensing element. Second, movement of the object image on the image sensing element as a display is detected when the movement occurs to obtain a movement signal indicating the movement. Third, the optical image is controlled to move in a prescribed direction to compensate for the movement signal based on the detection of the movement. Further, the object image is controlled always to be displayed at a prescribed position in the display of the television or the like even when the movement occurs by cutting a needless displaying area.
These background art systems, however, suffer from drawbacks. Specifically, the first system generally has high costs and makes the optical device bulky. The second system can not detect movement of the optical device in real time. In particular, since detection of movement of an image having two dimensions is generally executed using a pattern matching method for detecting matching of patterns, a complex operation and an excessive time period are required. To simplify the image movement detection, an average of information stored in a prescribed line or column of an image sensing element is used as one dimensional information, and movement of the optical image in a direction of the column or the line is detected to produce two optical images to be compared. However, as a result, a contrast of the optical image is generally decreased.
To overcome the above-mentioned problems, the first type system and the second type system each mentioned above are generally combined with each other to compensate for each others shortcomings. Namely, such a combined system includes a mechanical movement detecting device for detecting mechanical movement of the optical device itself, and an image movement detecting device for detecting object image movement to optionally use each device.
Such a combined system is described, for example, in Japanese Patent Application laid Open Nos. 2-75284, entitled xe2x80x9cPhotographing Apparatusxe2x80x9d, 4-163534, entitled xe2x80x9cImage Movement Suppressing Apparatus for a Cameraxe2x80x9d, 4-163535, entitled xe2x80x9cImage Movement Suppressing Apparatus for a Cameraxe2x80x9d, 4-215623, entitled xe2x80x9cImage Movement Suppressing Apparatus for a Cameraxe2x80x9d, and 5-14801, entitled xe2x80x9cImage Movement Suppressing Apparatusxe2x80x9d.
However, the combined device generally has high costs, and does not operate in real time due to a complex movement detecting operation required when detecting an image movement signal indicating movement of an optical image, and can not be precise due to generally using an angular velocity sensor or the like.
In consideration of the above and other problems, it is an object of the present invention to provide a novel hand movement correcting apparatus.
A specific embodiment of the present invention includes a mechanical movement detecting device for detecting a mechanical moving amount of a body and generating a mechanical movement signal indicating a mechanical moving amount when hand movement occurs, an image movement detecting device for detecting a moving amount of an object image formed on imaging elements and generating an image movement signal indicating the image moving amount in response to the mechanical movement signal, and a hand movement correcting device for correcting hand movement based on the image movement signal and the mechanical movement signal.
In another embodiment, a plurality of object images are formed on the imaging elements during the hand movement, and the hand movement detecting apparatus detects the image moving amount based on the pair of the object image signals generated by the imaging elements.
In yet another embodiment, the image moving amount may be detected by detecting a difference in phase of waveforms of the pair of the object image signals.
In yet another embodiment, the image movement detecting device may determine timing of imaging of the object image based on the mechanical movement signal.
In yet another embodiment, the image movement detecting device may generate a plurality of object image signals by periodically forming a plurality of object images on the imaging element, and select a pair of object image signals to compare the image moving amount.
In yet another embodiment, the image movement detecting device may change an angle of an optical axis of the optical unit based on the mechanical movement signal, and may then detect an image moving amount by detecting object image signals generated after the change of the optical axis.
In yet another embodiment, the image movement detecting device may detect an image moving amount moved in a direction different when a prescribed amount of the mechanical movement is detected.
In yet another embodiment, the mechanical movement detecting device may output a signal as a mechanical movement signal indicating an inclination level of a body about a gravity direction.
In yet another embodiment, the mechanical movement detecting device may output a signal indicating a velocity angle of the body as a movement signal.